Surface morphology and in vitro leachability of soft liners modified by the incorporation of antifungals for denture stomatitis treatment

Objective: To evaluate the surface morphology and in vitro leachability of temporary soft linings modified by the incorporation of antifungals in minimum inhibitory concentrations (MIC) for Candida albicans biofilm. Methodology: Specimens of soft lining materials Softone and Trusoft were made without (control) or with the addition of nystatin (Ny), miconazole (Mc), ketoconazole (Ke), chlorhexidine diacetate (Chx), or itraconazole (It) at their MIC for C. albicans biofilm. The surface analyses were performed using Confocal laser scanning microscopy after 24 h, 7 days, or 14 days of immersion in distilled water at 37ºC. In vitro leachability of Chx or Ny from the modified materials was also measured using Ultraviolet visible spectroscopy for up to 14 days of immersion in distilled water at 37ºC. Data (μg/mL) were submitted to ANOVA 1-factor/Bonferroni (α=0.05). Results: Softone had a more irregular surface than Trusoft. Morphological changes were noted in both materials with increasing immersion time, particularly, in those containing drugs. Groups containing Chx and It presented extremely porous and irregular surfaces. Both materials had biexponential release kinetics. Softone leached a higher concentration of the antifungals than Trusoft (p=0.004), and chlorhexidine was released at a higher concentration than nystatin (p<0.001). Conclusions: The surface of the soft lining materials changed more significantly with the addition of Chx or It. Softone released a higher concentration of drugs than Trusoft did, guiding the future treatment of denture stomatitis

Morphology of root canal surface: A reflection on the process of cementation of the composite relined glass fiber post

Background: The present study was conducted to evaluate the bond strength in the different root thirds (premolars and maxillary central incisors) of composite relined glass fiber posts compared to untreated glass fiber posts cemented with dual- or chemical-cure cements. Materials and Methods: Sixty human single-rooted premolars (flat canal) (n = 15) and 12 maxillary central incisors were used (round canal) (n = 3). The teeth were sectioned, and the roots received endodontic treatment. The standardized preparation of the canals was carried out, and the roots were randomly divided into four groups according to the cementation systems: G1: cemented posts (dual: Ambar/Allcem); G2: relined posts (dual: Ambar/Allcem); G3: cemented posts (chemical: Fusion Duralink/Cement Post); and G4: relined posts (chemical: Fusion Duralink/Cement Post). The roots were cut to give two slices of each third of the root canal per specimen. Push-out test was conducted at a speed of 0.5 mm/min. Data were analyzed by analysis of variance and Tukey's post hoc test (α = 0.05). Results: There was no statistically significant difference between groups for the premolars (flat canal) (P = 0.959). There was a significant difference in the central incisors between the middle and apical thirds in the cemented group when using the dual system (P = 0.04) and between the middle and apical thirds (P = 0.003) and cervical and apical thirds (P = 0.033) when using the chemical system. Conclusion: Due to the anatomy of the root canal, flat canal of the premolars does not require relining, but round canal of the maxillary central incisors demands it for more secure in the bond strength